Altitude did not hold

Hi all, I am currently working on indoor autonomous flight using offboard mode.
The situation i’m facing is such that - my drone is able to hold its altitude at 1m, but when it rise from 1m to 1.5m, the drone till either overshoot or it will just fly to the ceiling.

Besides changing the PID, I adjusted the MPC_THR_HOVER = 49%
and MPC_XY_P = 0.5

Please advise thanks!